A Miami Herald article cites numerous instances over the years, ranging from at least 20 people killed in Iraq in by celebratory gunfire after the death of Saddam Hussein's sons Uday and Qusay. Aside from the perplexing question of why such a reckless, potentially lethal practice remains so popular, you may also be wondering, what actually happens to a bullet that's fired straight up into the sky?
How high does it go? What stops it and sends it falling back to Earth? And when it descends, when and where does it land? Those aren't necessarily simple questions to answer. Ballistics researchers have spent a lot of time studying the performance of bullets fired horizontally, because that's useful information for improving the accuracy and range of shooters. But when it comes to firing straight up in the air, which isn't something that soldiers, police officers, hunters or target shooters normally would do, there's not nearly as much data.
Army Maj. Julian Hatcher, who apparently was curious and had some time on his hands, did experiments in Florida in which he fired various weapons — ranging from rifles to machine guns — up into the air, and tried to measure how long it took for the bullets to come down, as well as where they landed. As he noted in his volume "Hatcher's Notebook," he calculated that a standard. But ballistics researcher James Walker, who holds a doctorate in mathematics and is department director of engineering dynamics at the Southwest Research Institute in San Antonio, says that the altitude attained by a bullet fired straight up would depend upon the type of weapon and projectile, just as it does when fired horizontally.
A handgun, which has a shorter barrel than a rifle and fires ammunition with a smaller cartridge that doesn't contain as much powder, isn't going to send a bullet soaring as high as a rifle will. Different types of rifles and ammunition vary as well. Rifles like the. When fired horizontally, bullets tend to slow down rapidly due to air drag, so that a rifle bullet may be down to half of its initial speed by the time it gets to meters 1, For altitude estimates, Walker pointed to this chart on the website of Close Focus Research , a ballistics testing company, which shows that a.
But no matter how high a bullet goes in the air, however, eventually it will decelerate until its velocity reaches zero, at which point it will begin to fall back to Earth, as detailed in this article on falling bullet injuries in the Journal of Neuroscience Rural Practice. Cartridges of older design were limited by the pressures they could withstand, but advances in metallurgy have allowed doubling and tripling of the maximum pressures so that more KE can be generated.
Many different cartridges are available using different loads and bullet designs. Some of these are outlined in the table below to compare and contrast the ballistics. What can be learned from specific cartridge data? If the 44 magnum is compared with the magnum, the effect of bore diameter is seen. The larger area of the 44 magnum creates more force with the same pressure, allowing the 44 magnum to produce more energy at the muzzle.
The effect of case capacity can be demonstrated in a comparison of the 9 mm parabellum para with the magnum. These cartridges have similar diameters and pressures, but the magnum is much longer, yielding more case volume more powder , and delivers more energy. Finally, despite the Colt 45 having the largest bore diameter and one of the longest cases, it does not deliver the maximum energy because the outdated design of this cartridge case severely handicaps its pressure handling capability.
The Glasser "safety slug" has been designed to consist of a hollow copper jacket filled with 12 birdshot. It has been designed in several calibers. When the bullet hits the target, the pellets are released over a wide area. However, the pellets quickly decelerate over a short distance, so they may penetrate poorly and are less likely to hit surrounding targets.
They are designed to stop, but not kill, an attacker while avoiding injury to bystanders. At close range, they may produce substantial injury.
The Winchester "Black Talon" cartridge, which comes in several calibers, is designed with a lead core locked to a copper alloy jacket by a unique notching process that is done to prevent separation of teh core and the jacket on target impact via controlled expansion. This expansion is desinged to occur in a delayed fashion at the muzzle velocities of the bullet in order to provide deeper penetration.
In addition, the jacket is thicker at the tip than at the heel, with precutting of the thick portion to that, upon target impact, six sharp copper points are raised in a radial fashion. The purpose of this design is to increase expansion and cavitation with greater transference of energy.
In one study with test firings, black talons penetrating plastic sheeting simulating elasticity of skin expanded irregularly, while those fired into ordnance gelatin simulating soft tissue uniformly expanded.
The copper points create a potential hazard in bullet removal by surgeons or forensic scientists. Russel et al, In a study by Speak et al , it was found that, in handguns, either shorter barrel length or larger caliber produced larger pellet patterns. Armour-piercing bullets are designed to penetrate soft body armor such as bulletproof vests worn by law enforcement officers. Though they penetrate such armor, they produce no more wounding than ordinary bullets of similar size.
Some have teflon coatings to minimize barrel wear with firing. They may demonstrate less deformation when recovered. Diagrammatic representations of standard handgun and rifle cartridges are shown below. The metal casing encloses the powder, above which the bullet is seated. The powder is ignited through the flash hole when the primer is struck. A case with a rim is found with revolver and lever action rifle cartridges, and also with some some bolt action and semi-automatic rifles.
The radiographic appearance of a. Standard shotgun shells contain the powder, wadding, and shot, enclosed in a plastic or cardboard casing, as diagrammed diagrammed below:. The length determines the amount of powder, and the amount of ounces of shot can vary within the shell, based upon the size and number of shot pellets.
A "magnum" load has slightly more powder and more pellets, so that the muzzle velocities are not greatly increased, but the total kinetic energy is greater because of the greater mass of pellets. A greater number of pellets increases the likelihood of hitting a target at longer ranges, because of the dispersal pattern of the pellets that increases with range.
The amount of kinetic energy possessed by any individual pellet can vary, based upon multiple variables and interactions among the shot mass. The size of pellets varies from large "" to small "9". Larger pellets have more kinetic energy, but fewer pellets disperse rapidly and accuracy in hitting the target is an issue. Greater numbers of smaller pellets have a better chance of hitting the target, but each pellet has a small amount of kinetic energy. For example, a skeet shooter trying to hit the clay pigeon wants many smaller pellets capable of hitting the target at a shorter range, while a deer hunter wants larger pellets capable of inflicting greater damage at longer range.
Shot may be primarily composed of lead or steel, along with combinations of other metals. The main reason for use of steel shot is environmental, to reduce lead contamination, but steel has inferior ballistic qualities from an energy standpoint less mass , but can be partially overcome by increasing powder loads and velocities.
The spread of the pellets as they leave the muzzle is determined by the "choke" or constriction of the barrel at the muzzle from none to 0. More choke means less spread. Full choke gives a 15 inch spread at 20 yards, while no choke gives a 30 inch spread at the same distance. DeMuth et al, A "sawed-off" shotgun has a very short barrel less than 18 inches so that, not only can it be concealed more easily, but also it can spray the pellets out over a wide area, because there is no choke.
Shotgun slugs can produce significant injury, because of the slug's size and mass. At close range, survival is rare.
In treating shotgun injuries, it is necessary to remember that the plastic shell carrier and the wadding which may not appear on radiographs can also cause tissue damage and may need to be found and removed. Gestring ML et al, Shotgun shells can be loaded with a variety of objects as projectiles, ranging from rubber pellets to needle shaped metal "flechettes" to rock salt to pepper balls. These have a novelty aspect, but their usefulness is questionable.
Some, such as the "bean bag" with a fabric bag containing shot, is purportedly "less lethal" have been utilized in law enforcement. Wounding is a function of the type of shot, or pellets, used in the shotgun shell. Weight, in general, is a constant for a shell so that 1 ounce of shot would equal either 9 pellets of 'double O' buckshot or pellets of 8 birdshot.
A 00 or "double ought" pellet is essentially equivalent to a low velocity. At close range less than 4 feet an entrance wound would be about 1 inch diameter, and the wound cavity would contain wadding. At intermediate range 4 to 12 feet the entrance wound is up to 2 inches diameter, but the borders may show individual pellet markings.
Wadding may be found near the surface of the wound. Beyond 12 feet, choke, barrel length, and pellet size determine the wounding. If the energy is divided between the pellets, it can be seen that fewer, larger pellets will carry more KE, but the spread may carry them away from the target.
Pellets, being spherical, are poor projectiles, and most small pellets will not penetrate skin after 80 yards. Thus, close range wounds are severe, but at even relatively short distances, wounding may be minimal. Range is the most important factor, and can be estimated in over half of cases, as can the shot size used.
Wilson, A rifled slug fired from a shotgun may have a range up to yards. Mattoo et al, The Polyshok Impact Reactive Projectile IRP is a form of shotgun ammunition with a lead bead core encased within a single, plastic projectile. The lead core is designed to disintegrate on impact so that lead fragments are distributed over a small area.
This reduces the likelihood of exit or collateral damage on missed shots. This projectile produces a single entrance wound, and both plastic and lead components can be found within the wound, regardless of the range of fire. The single entrance wound with limited area of tissue damage suggests a shotgun slug, while the small lead fragments within the wound suggest small size shot pellets, but together these findings are characteristic for the IRP Nelson and Winston, When you pull the trigger, the firing pin strikes the primer, causing it to explode.
The primer then starts burning the propellant gun powder. This flash process accumulates enough pressure and gases to detach the bullet from the cartridge and thrust it down the barrel. The barrel will spin the bullet until it leaves the muzzle. When it comes to firing a bullet, a weapon is only one part of the equation. It contains mechanisms that facilitate the whole process to the point where the bullet is discharged.
The trigger is one of the crucial components which initiate the firing process. The other components include the spring, firing pin, trap mechanism, and immediate mechanism. Once you pull the trigger, the spring that stores the elastic energy are released, which then move to make the action fire.
The immediate mechanism helps transfer the kinetic energy from the spring to the firing pin, which then strikes the primer. A firearm can either use a striker or a hammer to hit the firing pin. A striker is usually connected to the spring.
When the spring is released, the hammer transfers the tension to the pin, like a mallet would hit a chisel. Essentially, the action of pulling the trigger, makes the firing pin strike the primer of the cartridge in the chamber. At that moment the action moves on to what happens inside the ammunition you use. However, a cartridge is made of three main parts; the primer, propellant, and the bullet.
The primer is the section that the firing pin strikes. It contains chemicals that explode when the pin strikes it. The bullet is the section that leaves the barrel towards the target. It hits the target at high velocities and energies. There are different types of rounds, from jacketed ammunition, hollow-points, buckshots, wadcutter bullets, etc.
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